Pool season · California
Irvine Pool Season: the Year on One Bar
Last updated: July 15, 2026 · dates · water temp
This is the one-page view of Irvine's pool year: both model windows, the estimated water-temperature curve, and today's live position on the season bar. The detailed checklists live on the opening and closing guides; this page is the calendar you check between them.
Each dot on the bar is one week of Irvine's typical year, colored by what the model says that week is for: gray weeks are off-season, hollow teal marks the opening window (March 17–April 7), solid teal is swim season, and hollow amber is the closing window ending November 27. The black marker is today — its position against the colors is the entire executive summary.
The Irvine pool calendar
Opening — target March 24
Target March 24; the practical window runs March 17–April 7, and the 7-day mean crosses the 61°F threshold around April 7. Cold-water starts are the cheap ones.
Closing — deadline November 27
The window opens November 17 once water leaves the algae zone; the model deadline is November 27, a week ahead of the December 25 freeze normal.
Estimated water temperature by month
This is Irvine's typical-year water curve: the same EWMA model as the live widget, run on the 1991–2020 normals instead of this week's weather.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 56° | 56° | 59° | 61° | 64° | 67° | 71° | 75° | 75° | 72° | 65° | 58° |
The curve peaks near 75°F — comfortable-water months here usually involve a heater or a solar cover.
Email me when Irvine hits the closing window
Data: NOAA 1991–2020 climate normals via Tustin Irvine Rch (2.1 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.